The Influence of Exotic Lady Beetle (Coleoptera: Coccinellidae) Establishment on the Species Composition of the Native Lady Beetle Community in Missouri

Abstract

The diversity and abundance of native lady beetles (Coccinellidae) in North America has declined in recent decades. This decline is often correlated with the introduction and establishment of exotic lady beetle species, including Coccinella septempunctata L. and Harmonia axyridis Pallas, suggesting that exotic species precipitated the decline of native lady beetles. We examined species records of native coccinellids in Missouri over 118 yr and asked whether the species composition of the community experienced a shift following the establishment of the exotic species. We found that the contemporary native coccinellid community is different from the community that was present nearly a century ago. However, there was no evidence for a recent abrupt shift in composition triggered by the establishment of exotic species. Instead, our data suggest that the native lady beetle community has been undergoing consistent and gradual change over time, with some species decreasing in abundance and others increasing. While not excluding exotic species as a factor contributing to the decline of native lady beetle species, our findings suggest that other continuous factors, like land use change, may have played a more influential role in determining the composition of the native coccinellid communities within our region.

Fates of Rare Species under Siege from Invasion: Persistence of Coccinella novemnotata Herbst in Western North America alongside an Invasive Congener

“…Over the past century, C. novemnotata is thought to have been much more abundant previously than in recent years in many parts of North America (Gordon, 1985;Wheeler and Hoebeke, 1995;Harmon et al, 2007;Hesler and Kieckhefer, 2008;Fothergill and Tindall, 2010;Diepenbrock et al, 2016). One published record for Utah in particular indicates that under some circumstances, adults of C. novemnotata occurred at much higher abundance than documented here for the recent past (i.e., from the late 1980s to the present).…”

“…In addition or alternatively, this change may have resulted also from other factors, such as changing patterns of land use, climate change, changes in prey abundance (e.g., aphids in crops), and disease (Wheeler and Hoebeke, 1995;Day and Tatman, 2006;Harmon et al, 2007). It is important therefore to consider also patterns in population status of C. novemnotata in other regions of North America as C. septempunctata has become well-established in these regions as well (Fothergill and Tindall, 2010;Bartlett et al, 2015;Diepenbrock et al, 2016).…”

“…The importance of alternative causes received support from subsequent documentation that C. novemnotata's steep decline in Missouri occurred well before C. septempunctata arrived (Fothergill and Tindall, 2010;Diepenbrock et al, 2016). Nonetheless, the arrival of C. septempunctata and its potential competitive and predatory impact on C. novemnotata, as explored in the laboratory (Hoki et al, 2014;Kajita et al, 2014;Turnipseed et al, 2014Turnipseed et al, , 2015Ugine and Losey, 2014;Tumminello et al, 2015), raises the possibility that C. septempunctata may now diminish prospects for recovery, and indeed may drive to critically lower levels, populations of C. novemnotata previously reduced to low numbers even before its arrival.…”

Differences in the Phenology ofHarmonia axyridis(Coleoptera: Coccinellidae) and Native Coccinellids in Central Europe

“…Within the native range of H. axyridis, there is also a considerable variability in host plant associations, with a low relative abundance on field crops in eastern Siberia (Kuznetsov andPinsker 1973, Arefin andIvliev 1988) but a high abundance on crops in Japan (Komai and Hosino 1951) and China (Liu et al 2012). In contrast, the occurrence of H. axyridis on trees is consistently high across its native range (Osawa 2011, Dong et al 2015, Kuznetsov 1972) and in areas it has recently colonized (Brown 2002, Michaud 2002, Frechette et al 2008, Milleo et al 2008 In North and South America, recently invaded H. axyridis apparently outcompetes native species on crops (Diepenbrock and Finke 2013, Grez et al 2016, Diepenbrock et al 2016. One reason for this scenario could be the larger body size of H. axyridis compared to that of the native species.…”

“…We studied the variations in the abundance of H. axyridis and the community of native species of coccinellids. This is because invasive H. axyridis likely affects, by different mechanisms, many species constituting the native community of coccinellids (Bahlai et al 2013, Diepenbrock and Finke 2013, Diepenbrock et al 2016. The presence of invasive H. axyridis and native coccinellids was recorded on trees, herbaceous plants and cereals from 2010 to 2016.…”